Improvement in shuttles foe sewing machines



.l. A. DAVIS.

Sewing-Machine Shuttle.

Patented May 28, 1867.

N, PETERS FHOTO-LITMOGRAFH ER.

@n'itrh 1am gaunt @ffise.

JOB A. DAVIS, WATERTOWN, NEW YORK Letters Patent No. 65,062, dated [May28, 1867. I

IMPROVEMENT IN SHUTTLES FOR SEWING MACHINES,

TO ALL WHOM IT MAY CONCERN:

Be it known that 1, JOB A. DAVIS, of iVatertown, in the county ofJefferson, and State of New York, have invented certain new and uscf'ulimprovements in Shuttles for Sewing Machines; and I do hereby declarethat the following is a full, clear, and exact description of theconstruction and operation of the same, reference heing had to theaccompanying drawings, making a part of this specification, in whlchFigure 1 is a side View of the shuttle.

Figure 2, a. top view or plan.

Figure 3, a longitudinal section.

Figure 4, afront end view; and

Figure 5, a bottom view.

Similar letters of reference indicate corresponding parts in the severalviews.

This invention relates to the manner of regulating the tension of thethread.

To enable others skilled in. the art to which my invention appertains toconstruct and operate the same, I will proceed to describe myimprovement.

Instead of the usual method of passing the thread through several holesin the side of the shuttle, Isubstitute the longitudinal lever-pad s, asshown in figs. 2 and 3, held in place by the pivotp upon the side of theshuttle, and operated by the lateral screw 20 and coil spring 0 insertedin the front end of the shuttle.

The lever-pad is so formed that each end rests against the side of theshuttle, the front end acting as the short end of the lever, so thatwhen the screw is forced against the spring itpresses the long end ofthe lever against the side of the shuttle, consequently giving thedesired tension to the thread. The thread passes from the bobbin upthrough the slot 6 and is carried over to the slot iin the rear end ofthe lever-pads, and thence (in the direction of the dotted line in fig.3) through the hole It in the side of the shuttle. The holes h and i areso placed that the thread passes between the lever-pad and the side ofthe shuttle, and is subjected to the pressure made by the action of thescrew and coil spring upon the lever-pad, and thereby the tensionregulated. The pressure upon the-thread is increased or diminished byturning the screw 20. The hole It in the side of the shuttle oppositethe slot 2' in the lever-pad is for the purpose of facilitating thethreading of the shuttle.

Having thus-described the construction and operation of my improvement,what I claim as my invention, and desire to secure by Letters Patent,isv The lever-pad s, screw w, and coil springs, when constructed andarranged substantially as and for the purposes set forth.

JOB A. DAVIS.

Witnesses: I

G. A. BAGLEY, JOHN Summon.

